Double bar lock

ABSTRACT

A double bolt police lock of the type having oppositely extending locking bars is provided which has an improved appearance, increased versatility and a more effective locking mechanism. The lock generally comprises a lightweight elongated housing within which a pair of locking bars are slidably mounted for movement between an extended locking position and a retracted unlocking position. In a first embodiment of the invention the locking bars are operatively drivingly connected for displacement in opposite directions by means of a rack and pinion mechanism disposed centrally within the housing. The locking mechanism is disposed in a lock casing near one end of the bar housing and comprises an improved latching device active on one of the locking bars and effective to deadlock that bar in one of its two operative positions. A second embodiment provides an adjustable length feature wherein a substantial length of one of the locking bars is replaced by a connecting rod arrangement to provide an operative driving connection between that bar and a driving pinion at the opposite end of the housing. That connecting rod arrangement is adjustable in length and/or removable from the housing whereby the housing and rod may be cut to size. A third embodiment of the invention provides a locking mechanism which is adjustably positionable along a substantial length of the housing. That locking mechanism utilizes a rack formed on the underside of one of the locking bars adapted to operatively drivingly engage with an adjustably positionable pinion. The pinion is in turn controlled by a knob at the inside of the premises and a lock cylinder extending through the door at the desired position.

United States Paten [1 1 Giardina et al. I

[451 Feb. 19, 1974 DOUBLE BAR LOCK [76] Inventors: Nicholas Giardina, 121 Wallace Ave,, Mount Vernon, NY. 10552; Melvyn A. Gervis, 295 Franklin St., l-laworth, NJ. 07641; Eugene Taras Wozny, 46 Van Orden Rd., Harrington Park, NJ. 07640; Richard D. Babock, 216 Fillmore St., Massapequa, N.Y. 11758 [22] Filed: Aug. 6, 1971 21] Appl. No.: 169,685

[52] US. Cl 292/39, 292/40, 292/150, 292/259 [51] Int. Cl. E05c 9/04 [58] Field of Search 292/277, 39, 259, 40, 150; 70/380 [56] References Cited UNITED STATES PATENTS 3,086,383 4/1963 Scott.... 292/39 X 2,071,092 2/1937 Troy 292/39 1,334,314 3/1920 Parsons... 292/39 2,406,459 8/1946 Gibson 292/39 3,290,079 12/1966 McKenzie... 292/172 2,936,606 5/1960 Welch et al 70/150 X FOREIGN PATENTS OR APPLICATIONS Great Britain 292/39 Primary ExaminerRichard E. Moore [5 7] ABSTRACT A double bolt police lock of the type having oppositely extending locking bars is provided which has an improved appearance, increased versatility and a more effective locking mechanism. The lock generally comprises-a lightweight elongated housing within which a pair of locking bars are slidably mounted for movement between an extended locking position and a retracted unlocking position.

In a first embodiment of the invention the locking bars are operatively drivingly connected for displacement in opposite directions by means of a rack and pinion mechanism disposed centrally within the housing. The locking mechanism is disposed in a lock casing near one end of the bar housing and comprises an improved latching device active on one of the locking bars and effective to deadlock that bar in one of its two operative positions.

.A second embodiment provides an adjustable length feature wherein a substantial length of one of the locking bars is replaced by a connecting rod arrangement to provide an operative driving connection between that bar and a driving pinion at the opposite end of the housing. That connecting rod arrangement is adjustable in length and/or removable from the housing whereby the housing and rod may be cut to size.

A third embodiment of the invention provides a locking mechanism which is adjustably positionable along a substantial length of the housing. That locking mechanism utilizes a rack formed on the underside of one of the locking bars adapted to operatively drivingly engage with an adjustably positionable pinion. The pinion is in turn controlled by a knob at the inside of the premises and a lock cylinder extending through the door at the desired position.

24 Claims, 12 Drawing Figures PATENTED FEB 1 91974 saw a RF 4 ATTORNEYS DOUBLE BAR LOCK The present invention relates to door locks and more particularly to police locks of the double bolt type.

There are today a variety of door locks on the market each provided to one extent or another with mechanisms adapted to afford security against entrance by unauthorized personnel. For protection against burglars, the conventional bolt lock is perhaps the most common type used today. Locks of this type include a housing generally secured to the door opposite the hinged side and one or more bolts adapted to lockingly engage with a bracket secured to the door frame. Locks of this type are generally provided with cylinder mechanisms controlling the bolt or bolts ranging from very simple inexpensive mechanisms to the recently developed complex and expensive no pick cylinders. In addition, several devices have been recently developed to frustrate attempts to remove the cylinder completely from the door to gain direct access to the tumblers.

, However, even with the aforementioned improvements, such locks still do not afford sufficient protection against experienced and/or determined burglars. Thus, an experienced thief confronted with an improved lock of the type described above will usually completely bypass the locking mechanism and attempt to gain entry at the hinged side of the door, either by removing the hinge pins (if they are accessible) or by simply forcing the door, causing the hinge or lock bracket to fail. For this reason it is generally agreed that maximum protection is afforded by what is commonly known as a double bolt police lock.

The typical double bolt police lock comprises a lock housing secured to the inner surface of the door and a pair of elongated bars extending therefrom. The bars are movable into and out of the housing between two positions in response to the rotation of a lock cylinder or the like by suitable drive means such as a rack and pinion arrangement. In the locked position the free ends of the bars are received in recesses in opposite sides of the door frame, or in the vertical type in recesses in the upper door frame and the floor. In the unlocked condition the free ends of the locking bars are retracted inwardly of the respective door interfaces so as to allow free swinging movement of the door.

Locks of this type may be locked or unlocked from the outside of the premises, usually by means of a key inserted into the lock cylinder. The key positions a set of tumblers to allow the cylinder to be rotated between its two operative (i.e., locking and unlocking) positions as described above. From the interior of the premises, the police lock may be locked and unlocked by moving the bars into the desired position. A handle operatively connected to the lock cylinder may be installed for this purpose.

The great advantage of a double bolt police lock is that it affords considerable protection against forceable entry'and/or removal of the hinge pins.

While police locks of the type described have been found to be particularly effective in maximum security applications, they have several drawbacks. Thus they are relatively expensive, cumbersome, and unsightly in appearnce. Moreover, because the locking bars are of substantial size and thickness, locksmiths and other retailers are generally not'equipped to cut the bars to the correct size. As a result they must be made in several standard sizes and for nonstandard size doors must be custom made, a factor which significantly increases cost. In addition because the locking casing must be centered on the door this type of lock is unsuitable for certain types of doors, such as glass doors, those having a substantial recess at the center, etc.

Finally, double bar locks of the rack and pinion type by their very nature are not deadlocked, that is. the locking bars may be manually pushed to the unlocked position without touching the lock cylinder. This lack of deadlocking presents a serious drawback because the moving of the bars to the unlocked position either by jiggling or by manipulation with an instrument at the door-frame interface is a real possibility, particularly if the bars are not fully extended.

It is for the above reasons that police locks of this type are not widely used. Indeed, while double bar police locks have been known for decades, their use has been virtually limited to commercial establishments where the cost can be justified and appearance is not of primary concern. As a result these locks have in the past been designed primarily for the protection of commercial establishments.

In recent years, as a result of the increased concern of apartment dwellers and home owners for the safety of their persons and property, there has developed a great need for maximum security police locks of the double bolt type for use in residential dwellings. The present invention provides an improved double bolt police lock which admirably fills that need.

It is a primary object of the present invention to provide a double bolt police lock of the type described which is of simple, compact construction, is versatile, provides a pleasant appearance and is adapted to provide maximum security for a dwelling.

It is another object of the present invention to provide a double bar lock comprising oppositely extending locking bars with a latch type locking mechanism whereby the locking bars may be deadlocked to provide increased protection.

It is yet another object of the present invention to design a double bar lock of the type described which may be conveniently adjusted to fit any size door and in addition is provided with means to vary the position of the lock cylinder relative to the door.

It is still another object of the present invention to design a double bar lock with an improved cylinder disengage mechanism effective to prevent unauthorized entry by one having a key when locked from the inside.

It is still another object of the present invention to design a rack and pinion drive mechanism for use in a double bolt police lock wherein the lock cylinder may be positioned at various locations along the housing bar.

It is yet another object of the present invention to provide a double bar police lock which is light weight, easy to install, extremely versatile and in addition has a longer trouble-free operating life than conventional police locks.

To these ends, the double bar lock of the present invention comprises a light weight elongated hollow housing within which a pair of elongated locking bolts or bars are slidably mounted. The bars are provided at their innermost ends with oppositely facing overlapping racks meshingly drivingly engaged with an idler pinion freely rotatably mounted within the hollow housing. The driving mechanism for the locking bars is positioned near one end of the housing and is active on one of the bars to position same between two operative positions-an unlocked position completely interior of the housing and a locked position in which the free end of the bar extends axially from the housing a substantial distance. The rotatable idler pinion serves to drive the other bar in the opposite direction by an equal amount, whereby appropriate movement of the locking mechanism controls the locking and unlocking of both bars.

In a first embodiment the locking mechanism is of the latch type adapted to provide deadlocking and comprises a recess in the driving bar receiving a driving projection rotatably mounted on the lock frame. Mounted within the recess for sliding movement therein is a platform. The driving projection is movable into and out of the recess through spaced apertures in the bar housing, those spaced apertures being connected by a narrow slot in the housing. In the unlocked condition the platform is received in the inwardly spaced aperture in the housing. To move the bars to the locking position, the projection is rotated through the aperture in the housing and into engagement with the platform whereby the platform is depressed, the projection is received in the bar recess and the bar is driven to its extended locking position by the projection which moves through the housing slot in an arcuate path. As the projection emerges from the housing the platform is again resiliently biased upwardly into the second aperture in the housing to deadlock the bars in their extended positions.

In a preferred embodiment two such projections are provided, each independently adapted to move the bars to the locked or unlocked positions. The first of these projections is drivingly connected to a knob accessible from the inside of the door and the second is drivingly connected to the lock cylinder which is in turn controlled by the appropriate key from the outside of the premises.

In a second embodiment the driving mechanism comprises a driving pinion mounted for rotation at the underside of the bar housing at one end thereof. The bar at that end is provided with a second rack on its underside which rack is exposed through an elongated slot in the housing. The driving pinion may be positioned anywhere along the slot in meshing engagement with the rack thereby considerably enhancing the versatility of the device.

The driving pinion is controlled by a knob fixedly secured thereto and mounted on the inside of the door. A splined engagement between the knob and lock cylinder mounted on the outside door surface provides an operative driving connection between the two for authorized entry by means of an appropriate key inserted in the lock cylinder. Resilient means are provided for normally maintaining that splined connection and means are provided on the inner knob for disengaging same, whereby attempted entry by means of the appropriate key results merely in a free rotation of the lock cylinder independent of the driving pinion.

In order to facilitate length adjustment to fit various sizes of doors, in accordance with this invention a narrow elongated rod may be substituted for a substantial length of the sizable locking bars interiorly of the hous-. ing. In accordance with this embodiment a single driving pinion is mounted interior of the housing near one end thereof and is adapted to meshingly engage a rack on the inner end of the first locking bar at that end of the housing. The locking bar at the other end of the housing extends inwardly of the housing only a short distance and is drivingly connected to the pinion by means ofa first elongated rod, an intermediate stabilizing bar and a second elongated rod provided with a rack in opposing overlapping relationship with the rack on the first locking bar. The first rod is received at either end in the locking bar and stabilizing bar, respectively, and is secured thereto by means of set screws. The housing is provided with a slot in registration with one or more of the set screws whereby one bar may be removed without removing the pinion or disassembling the locking mechanism. The lock may then be cut to size merely by cutting the rod and housing to the desired length, reinserting the rod and bar and tightening the appropriate set screw.

To the accomplishment of the above and to such other objects as may hereinafter appear, the present invention relates to an improved double bar police lock as defined in the appended claims and as described herein with reference to the accompanying drawings in which:

FIG. 1 is a front elevational view of a door upon which one embodiment of our improved lock is installed;

FIG. 2 is a cross sectional view taken along the line 2-2 of FIG. 1, showing the latching mechanism in the deadlocked position;

FIG. 3 is a cross sectional view taken along the line 33 of FIG. 2;

FIG. 4 is a cross sectional view taken along the line 4-4 of FIG. 3;

FIG. 5 is a cross sectional view similar to FIG. 3 showing the latching mechanism in an intermediate position between its locked and unlocked conditions;

FIG. 6 is a front elevational view of the lock of FIG. 1 on an enlarged scale with the housing broken away and partly in section, showing the two locking bars and the rack and pinion drive mechanism;

FIG. 7 is a fragmentary front elevational view, similar to FIG. 1, showing a second embodiment of the invention;

FIG. 8 is a cross sectional view taken along the line 88 of FIG. 7 showing a cylinder disengage mechanism;

FIG. 9 is a cross sectional view taken along the line 99 of FIG. 8 and showing the connecting rods inside the housing;

FIG. 10 is a fragmentary front elevational view similar to FIG. 1 of a third embodiment of the invention;

FIG. 11 is a cross sectional view taken along the line 11-11 of FIG. 10; and

FIG. 12 is a cross sectional view taken along the line 1212 of FIG. 11 and showing a rack and pinion driving mechanism at the underside of the housing.

The typical prior art double bar police lock comprises a rather bulky lock casing positioned centrally on the interior of the door from which two substantially thick elongated locking bolts or bars extend in opposite directions. The bars are positioned in spaced overlapping relationship within the casing and are provided with opposing racks driven by a common pinion operatively connected to the lock cylinder accessible from the outside of the premises. The bars in the locked position are generally received in recesses in the door frame at opposite sides of the door.

The present invention provides a double bar lock which is a significant improvement over the above construction as regards the factors of cost, appearance and the effectiveness of the actual locking mechanism.

The first embodiment of the invention'is generally illustrated in FIG. 1 and comprises an elongated narrow housing secured transversely on a door 12 by means of a bracket 14 at one end and lock casing 16 at the other end. A pair of locking bars 18 and 20 are mounted within housing 10 for sliding movement therein between an unlocked position entirely interior of the housing and a locked position (shown in broken lines) in which they extend outwardly of the housing at opposite ends thereof into appropriate receptacles in the door frame 22 or other fixed structure. Mounted on the lock casing 16 is a knob 24 adapted to control the bar action in a manner hereinafter described.

As best shown in FIG. 6 locking bars 18 and 20 are provided at their innermost ends interior of the housing 10 with cutaway stepped sections positioned in overlapping relationship. As there shown, each bar has a first step 28 of about half the width of the bar and a second step 30 of approximately a quarter of the original width of the bar defining a thin elongated tongue 32 at the end of each bar. Tongues 32 are provided with opposing overlapped gear surfaces or racks 34. Disposed between opposing racks 34 and meshingly engaged therewith in driving relationship is a pinion 36. Pinion 36 is rotatably mounted on the housing centrally thereof and in the embodiment illustrated, as a result of the deadlocking latch mechanism to be described hereinafter, that rotatable mounting may either be permanent within the housing or removable through a small aperture (such as 38 in FIG. 1) in the housing and secured therein by suitable means such as a simple cotter pin (not shown). In either case during assembly, care must be taken to properly engage racks 34 simultaneously with pinion 36 in order to insure that the bars 18 and 20 are extended from the housing by an equal amount.

In order to facilitate a smooth sliding engagement of bars 18 and 20 within housing 10, those bars are provided with a plurality of ball bearings 38 mounted within longitudinally extending grooves 40 on the upper and lower surfaces thereof'(as viewed in FIG. 6), the bearings 38 being in rolling engagement with the housing wall.

The locking mechanism for moving bars 18 and 20 between their locked and unlocked positions is disposed within casing 16 and is best illustrated in FIGS. 2 and 3. As there shown casing 16 comprises a rectangular plate 42 mounted on the inside surface of the door 12 by suitable means such as screws 44 at the corners thereof and a cover section 46 secured to plate 42 prior to installation by means such as allen head screws 48.

Cover section 46 comprises a vertically disposed front wall 50, top and bottom walls 52 and side walls 54 which together define a receptable for the lock mechanism. The receptable is divided into an upper section 56 and a lower section 58 by means of a shoulder 60 on the interior surface of front wall 50 and a cross member 62 extending between side walls 54 and spaced from front wall 50 to define a slot 64 communicating between upper and lower sections 56 and 58. As best shown in FIG. 2 side walls 54 terminate at shoulder 60 to define, together with that shoulder and cross member 62, a U-shaped channel 66 within which housing 10 is received.

As best shown in FIG. 4, housing 10 is provided at its top surface with spaced apertures 68 and 70, respectively, communicating with receptacle 56 and connected by a narrow slot 72 extending longitudinally therebetween. Apertures 68 and 70 and slot 72 are positioned in registration with slot 64 in the cover member 46 and bar 20 is thus exposed through housing 10 to the receptacle 56.

As best shown in FIGS. 3 and 4, bar 20 is provided at its top surface with a recess 69, the bottom surface of which is provided with a central depression 71 and a pair of slots or grooves 73 extending the remaining width of the bar to the bottom of housing 10.

As best shown in FIG. 2, mounted within recess 69 for vertical sliding movement therein is an inverted U- shaped member comprising a platform 74 and a pair of side legs 76 extending downwardly therefrom. Platform 74 is adapted in its upwardly disposed position to be re ceived in either of apertures 68 or 70 and is spring biased upwardly into engagement with shoulder and cross member 62 on cover member 46 as illustrated in FIG. 2 by means of a compression coil spring 78 received at its upper end in a depression 80 in the underside of platform 74 and at its lower end in depression 71 in the lower surface of recess 68. In this upwardly disposed position platform 74 is effective to deadlock bar 20 against sliding movement within housing 10. FIGS. 3 and 4 illustrate the bar 20 in the extended locking position with platform 74 received within aperture 70. In the unlocked position of the bar 20 (not shown) platform 74 is received within aperture 68.

The mechanism for moving bar 20 between the locked and unlocked positions is disposed within receptacle 56 and comprises a shaft 82 journalled in the front wall 50 of cover member 46 and extending outwardly therefrom. Knob 24 is mounted fast on shaft 82 and provides control of the locking mechanism from the inside of the premises. The other end of shaft 82 within receptacle 56 is provided with a projecting portion of reduced cross section 84 upon which is fixedly mounted a radially projecting finger 86. Finger 86 is provided with a rounded end surface 87 which is received within slot 64 in cover member 46 and in the position illustrated in FIG. 3, engages the platform 74 exposed through aperture in the housing 10.

In operation, as knob 24 is rotated clockwise, as viewed in FIG. 3, it is effective to depress platform 74 within recess 69 against the bias of coil spring 78. When the upper surface of platform 74 has been depressed sufficiently to clear the upper surface 88 of housing 10 at either side of slot 72, bar 20 is freed to slide within housing 10. Further rotation of finger 86 in the clockwise direction brings finger surface 87 into recess 69 in driving engagement with the left hand side wall thereof. Accordingly, as best shown in FIG. 5, bar 4 20 is carried in the direction of arrow 91 within housing 10, finger 86 moving in an arcuate path through slot 72 in the upper surface of the housing. As the recess 69 is brought into registration with the inwardly disposed aperture 68 in housing 10, finger 86 moves out of the recess and platform 74 is again urged upwardly by coil spring 78 within that aperture and into engagement with shoulder 60 and cross member 62 (FIG. 2). In this position (not shown) bar 20 is retracted completely within housing 10 to the unlocked position. The movement of bar 20 back to the locked position illustrated in FIG. 3 is accomplished by a counterclockwise rotation of knob 24 which effects the reverse operation;

The displacement of bar 20 between its two operative positions is accompanied by an equal and opposite displacement of bar 18 as a result of the rack and gear mechanism illustrated in FIG. 6. Thus both bars may be simultaneously retracted or extended to their unlocking or locking positions, respectively, and they are maintained in one of those two positions by the engagement of platform 74 with housing lthat is, these positions are deadlocked positions.

To insure against override by momentum, a stop mechanism generally designated 90 is preferably provided and is active between the bar 20 and casing 16. As best shown in FIGS. 2-4, stop mechanism 90 comprises an allen head screw 92 threadedly secured to the inner surface of bar 20 and projecting outwardly there from adjacent recess 69. Screw 92 is received in a longitudinal groove 94 in plate 42. Groove 94 is ofa length corresponding to the length displacement of bar 20 between its retracted and extended positions, and is so located on plate 42 that the screw 92 comes into engagement with the ends of groove 94 when bar 20 is fully retracted or extended. Thus the groove is effective to prevent override of the bar 20 in either direction.

The stop mechanism 90, while effective to prevent override, raises the possibility of an additional problem-that of rebound. Thus, particularly when the bar 20 is moved rapidly to the locked (extended) position, the engagement of screw 92 with the right hand end of groove 94 (as viewed in FIG. 3), may cause the bar to bounce back to the left before platform 74 has been securely received in aperture 70 in housing (this is most likely to happen as a result of lost resiliency in spring 78 after long periods of use). In the event of this occurrence, the bar will not be fully extended and effectively deadlocked. To compensate for this potential problem platform 74 is preferably provided with a narrow tongue 96 projecting upwardly from its upper surface. As best shown in FIG. 4, tongue 96 extends in the axial direction of bar 20 from the right band edge of platform 74 and terminating somewhat short of the left hand edge thereof, and is generally aligned with the upper surface 88 of housing 10 at one side of slot 72. Accordingly, as bar 20 is moved to the extended position shown in FIG. 3, tongue 96 projects into aperture 70 prior to the terminal fully extended position of bar 20 and undesired rebound is effectively prevented by the engagement of the tongue 96 with the upper surface 88 of the housing 10. In other words, the bar 20 is effectively deadlocked in an extended position prior to beingfully extended and prior to the engagement of screw 92 with the end of groove 94.

As best shown in FIG. 2, a second finger 98 identical to finger 86 is positioned in slightly spaced axial relationship therefrom and in registration therewith for providing actuation of the locking bar 20 between its locked and unlocked conditions from the outside of the premises through an appropriate lock cylinder. Finger 98 is mounted fast on one end 100 of a shaft 102 which is journalled within an aperture 104 in plate 42 and extends therethrou gh. Shaft 102 is provided with a collar 106 inside casing 16 and bearing against plate 42 and is provided at its other end with a slot 108 adapted to effect a splined engagement with a suitable lock cylinder (not shown). The slotted end of shaft 102 extends through aperture 104 in plate 42 into a registering aperture 110 in the door within which the lock cylinder is adapted to be received. Thus rotation of the lock cylinder by means of an appropriate key is in turn effective through the splined engagement with shaft 102 to rotate finger 98 between its locking and unlocking positions, thereby to extend or retract, respectively, bar 20 in the manner described above.

The foregoing embodiment provides an effectively deadlocked double bolt police lock with a rather simple and inexpensive construction and having a rather streamline and compact appearance.

However, the use of locking bars such as 18 and 20 shown in FIG. 5 of substantial thickness somewhat limits the versatility of the double bar police lock described above. Thus the lock must be manufactured in a number of standard sizes so as to accurately fit the various standard size doors. In the event it is desired to install such a lock on a non-standard sized door, the lock must be either custom made to size or the locking bars and housing of a larged sized lock must be cut down to the desired size. Unfortunately, locksmiths and other retailers of locks of this type are generally not equipped to provide this modification, particularly if, as is desirable, the locking bars are formed of a material, such as hardened steel, which is particularly resistant to cutting. The second embodiment of our invention illustrated in FIGS. 7-9 provides a simple and effective solution to this problem. As there shown, the lock comprises a housing 1 12 within which locking bars 114 and 116 are slidably mounted for movement between an extended locking position as shown in FIG. 9 and a retracted unlocked position in which the bars are completely received within housing 112.

As best shown in FIG. 8, housing 112 is mounted on door 12 by means of a pair of brackets 113 and provided near one end thereof with registering laterally extending apertures 118 and 120 in opposing parallel side walls thereof within which a hollow shaft 122 is journalled for rotation. Mounted on shaft 122, concentrically thereof within housing 1 12, is a pinion 124. Pinion 124 is in driving meshing engagement with oppositely extending overlapping racks 126 and 128 within housing 112. The bottom rack 126 as viewed in FIG. 9 is formed directly on an elongated tongue I30 integral with bar 116 and extending inwardly therefrom. The other rack 128 is formed on the underside ofa connecting rod 132. Connecting rod 132 extends longitudinally within housing 112 and is received at one end in sliding engagement within a registering bore 134 formed in locking bar 116. The other end of connecting bar 132 is operatively secured to a stabilizing bar 136, slidably mounted within housing 112, by suitable means such as an adjustable set screw 138. A second connecting rod is received in a bore 141 in the other side of stabilizing bar 136 and secured therein by set screw 142. Rod 140 is secured at its other end to the opposite lock ing bar 114 by means of another set screw 144. Thus, an operative driving connection is established between locking bar 114 and pinion 124 through connecting rod 140, stabilizing bar 136 and the racked connecting bar 132.

In the embodiment illustrated, the lock may be shortened for use with doors of reduced width merely by removing the rod 140 and bar 114 from the housing and cutting the rod 140 and housing 112 to size. For this purpose a slot is provied in housing 112 in registration with set screw 142 whereby that set screw may be tightened and loosened from the outside of the housing (see FIG. 7).

Alternatively as shown in FIG. 12, bore 141 may be extended completely through stabilizing 7 bar 136, whereby the effective length of rod 140 may be manually adjusted by a proper positioning of rod 140 within bore l4l,prior to'tightening screw 142.

It will be appreciated from the foregoing that with this construction the bars may be moved between their locking and unlocking positions simply by rotating pinion 124. The rotating mechanism is best illustrated in FIG. 8 wherein there is shown a knob 146 fixedly mounted on that portion of shaft 122 which extends to the interior of the premises by means of a set screw 147. Knob 146 is provided with an axially extending aperture 148 registering with an axially extending aperture 150 in shaft 122. Mounted within apertures 148 and 150 for sliding movement therein is a connecting shaft generally designated 152 having a first section 154 received within aperture 150 and a second section 156 received within aperture 148 in knob 146 and separated from section 154 by a radially extending collar 158. As illustrated aperture 148 is counterbored at 160 to define a shoulder 162. Mounted concentrically on shaft section 156 within counterbore 160 is a spring 164 bearing against shoulder 162 at one end and against collar 158 at its other end. Accordingly, shaft 152 is normally spring biased into the position shown in solid lines in FIG. ,8. Knob 146 is provided with a counterbored slot 166 in registration with aperture 148. A button 168 is fixedly mounted on the outwardly extending'end of shaft 152 by means of a set screw 170 and is provided with a narrow stem portion 172 which, as shown in solid lines in FIG. 8, is received within slot 166 in knob 146.The other end of shaft 152 is provided with a slot 174 which in the solid line position illustrated, receives a projection 176 extending from the lock cylinder 178 mounted within the door 12, thereby to effect a splined connection between the lock cylinder 178 and the shaft 152.

In operation, pinion 124 may be rotated from the inside of the premises directly through shaft 122 and knob 146. Locking and unlocking may be accomplished from the outside of the premises by an appropriate key 180 which, when the tumblers are properly engaged, is effective to rotate the lock cylinder which in turn through the splined connection 174, 176 rotates shaft 152 and thus to knob 146 through the engagement of stem 172 on button 168 with the'slot 166 on knob 146.

In the event it is desired to prevent entry from the outside even by one'having the appropriate key, button 168 may be pulled outwardly to the broken line position illustrated in FIG. 8 and turned a quarter of a turn to bring stem 172 out of alignment with slot 166. As illustrated, in this position of shaft 152, slot 174 is disengaged from projection 176 on lock cylinder 178. Accordingly, under these circumstances, rotation of lock cylinder 178 by means of the appropriate key will have no effect whatsoever on shaft 152 and it is thus drivingly disengaged from pinion 124.

The rack and pinion drive mechanism described above is particularly suited for double bar locks of the type here considered as a result of its simplicity of design and operation. However, for a given sized lock the pinion location must be designed into the housing. Thus, when the lock is installed on an appropriate size door, the lock cylinder must of necessity be aligned with the driving pinion which is already mounted at a specified location on the bolt housing. As a result, the lock may not be used on certain doors, such as those having glass panes or other unsuitable materials and/or surface characteristics at the necessary lock cylinder location. Moreover, when changing locks it is generally customary and desirable to utilize the same lock cylinder or at least the same lock cylinder aperture in the door as was used in a previous lock, a technique which is generally not feasible with the rack and pinion type lock described above.

An effective solution to the aforementioned difficulties is provided by a third embodiment of our lock illustrated in FIGS. 10-12. As best shown in FIG. 12, that embodiment utilizes a reciprocal rack and pinion arrangement identical to that in the second embodiment described above with the exception that pinion 124 in this embodiment is an idler pinion freely rotatably mounted in housing 10 in any appropriate manner. The actual locking mechanism, as illustrated in FIG. 12, comprises a second rack 182 on the underside of bar 116 near its extended locking end. An aperture 184 is formed in the underside of housing 10 generally in the area of rack 182 thereby to expose rack 182 along a substantial length thereof.

The bar housing 112 is mounted on door 12 by means of brackets 185 and 187 and a driving pinion 186 is rotatably mounted within a bracket 187 in meshing engagement with rack 182. Accordingly, rotation of driving pinion 186 effects a reciprocal sliding movement of bars 114 and 116 between their locking and unlocking positions. Pinion 186 is controlled from the inside of the premises by knob 146 and from the outside thereof by' lock cylinder 178 in a manner identical to that already described with regard to FIG. 8.

It will be appreciated that the pinion 186 and thus the lock cylinder 178 may be positioned at any location along the exposed portion of rack 182. Accordingly, rack 182 and aperture 184 are preferably of substantial length to provide a wide range of lock cylinder positions, thereby considerably enhancing versatility of the lock. The adjustable lock cylinder position feature together with the variable length feature of the lock of this embodiment provides a high security double bolt lock suitable for use on virtually any door. It will of course be apparent that the latch type locking mechanism of FIG. 3 may be utilized in the embodiment of FIG. 12 in lieu of the rack and pinion drive there shown.

It will be appreciated from the foregoing that we have provided an improved double bolt police lock of a revolutionary design combining improved locking features with increased versatility and a pleasant compact appearance.

The latching mechanism herein described insures deadlocking of both bars in a simple but effective manner, thereby to positively prevent manipulation of the bars. The use of thin connecting rods not only provides a convenient mode of length adjustment but also provides a significant reduction in the length of bar utilized, a factor which significantly reduces cost. Finally, the exposed rack and pinion drive considerably facilitates installation on a variety of doors, many of which were hitherto unsuitable for double bolt police locks.

While only a limited number of embodiments of this invention have been herein specifically disclosed, it will be apparent that many variations may be made thereto without departing from the spirit and scope of the invention, as defined in the following claims.

We claim:

1. A double bolt security lock for securing a door against unauthorized entry, comprising a housing, first and second locking bars mounted in said housing for sliding movement therein, and adapted to extend outwardly therefrom at opposite ends thereof, driving means within said housing operably drivingly connecting said first and second bars and effective to move one of said bars in said housing in a given direction in response to the movement of the other of said bars in the opposite direction, locking means independent of said driving means comprising moving means operably connected to said first bar and effective when actuated to move said first bar between locking and unlocking positions, said second bar, when said first bar is moved to said locking position, moving away from said first bar to a locking position, said bars then extending respectively from opposite ends of said housing and said second bar, when said first bar is moved to said unlocking position, moving inwardly towards said first bar to an unlocked position; a lock casing, a first aperture in said housing, depressible means on said first bar and extending transversely therefrom into said first housing aperture such that said first bar is latched in said locking position whereby said opposing extending bars are deadlocked in their extended locking positions, and manually actuatable means on said lock casing movable into said housing aperture and effective when so moved to depress said depressible means to a position inwardly of said housing thereby to unlatch said first bar from said housing.

2. The security lock of claim 1, further comprising a recess extending transversely into said first bar, said depressible means being slidably mounted within said recess, and resilient means urging said depressible means into said first housing aperture when said first bar is in said first position.

3. The security lock of claim 2, further comprising a longitudinally extending slot in said housing communieating at one end with said first housing aperture, said manually actuatable means being said moving means and comprising a finger moveable through said first housing aperture into said recess to depress said depressible means within said recess and adapted to drivingly engage said recess and to move within said slot in said housing thereby to carry said first bar from said second to said first position.

4. The security lock of claim 3, wherein said finger is rotatably mounted on said lock casing and is adapted to move through said slot in an arcuate path.

5. The security lock of claim 4, further comprising a second aperture in said housing spaced from said first housing aperture and communicating with the other end of said slot, said finger being adapted to move into said housing through one of said apertures to traverse said slot and to move out of said housing through the other of said apertures, said second aperture receiving said depressible means in said second position of said first bar.

6. The security lock of claim 5, wherein said bars in their unlocked positions are fully retracted within said housing.

7. The security lock of claim 5, further comprising stop means operatively connected to said first bar and said lock casing and active therebetween to limit the travel of said first bar substantially between said first and second positions.

8. The security lock of claim 1, wherein there are two manually actuable means each effective to move said first bar from said second to said first position, one of said manually actuatable means being accessible from one side of said lock casing and the other of said manually actuatable means being key actuatable from the other side of said lock casing.

9. The security lock of claim 8, wherein said bars in their unlocked positions are fully retracted within said housing.

10. The security lock of claim 1, further comprising stop means operatively connected to said first bar and said lock casing and active therebetween to limit the travel of said first bar substantially between said first and second positions.

11. The security lock of claim 9, further comprising a recess extending transversely into said first bar, said depressible means being slidably mounted within said recess, and resilient means urging said depressible means into said first housing aperture when said first bar is in said first position.

12. The security lock of claim 10, further comprising a recess extending transversely into said first bar, said depressible means being slidably mounted within said recess, and resilient means urging said depressible means into said first housing aperture when said first bar is in said first position.

13. The security lock of claim 12, further comprising a longitudinally extending slot in said housing communicating at one end with said first housing aperture, said manually actuatable means being said moving means and comprising a finger moveable through said first housing aperture into said recess to depress said depressible means within said recess and adapted to drivingly engage said recess and to move within said slot in said housing thereby to carry said first bar from said second to said first position.

14. The security lock of claim 5, wherein there are two fingers each movable through said aperture into said recess to depress said depressible means in said recess and to drivingly engage said recess and adapted to move within and along said slot in said housing thereby to move said first bar from said second to said first position, said fingers being mounted on first and second rotatable shafts within said casing, said first shaft being manually rotatable from one side of said lock casing and said second shaft being key actuatable from the other side of said casing.

15. The security lock of claim 7, wherein there are two fingers each movable through said aperture into said recess to depress said depressible means in said recess and to drivingly engage said recess and adapted to move within and along said slot in said housing thereby to move said first bar from said second to said first position, said fingers being mounted on first and second rotatable shafts within said casing, said first shaft being manually rotatable from one side of said lock casing and said second shaft being key actuatable from the other side of said casing.

16. The security lock of claim 1 wherein said bars in their unlocked positions are fully retracted within said housing.

17. The security lock of claim 16, further comprising a recess-extending transversely into said first bar, said depressible means being slidably mounted within said recess, and resilient means urging said depressible means into said first housing aperture when said first bar is in said first position.

18. The security lock of claim 17, further comprising a longitudinally extending slot in said housing communicating at one end with said first housing aperture, said manually actuatable means being said moving means and comprising a finger moveable through said first housing aperture into said recess to depress said depressible means within said recess and adapted to drivingly engage said recess and to move within said slot in said housing thereby to carry said first bar from said second to said first position.

19. A double bolt security lock for securing a door against unauthorized entry, comprising a housing, first and second locking bars mounted in said housing for sliding movement therein and adapted to extend outwardly therefrom at opposite ends thereof, driving means within said housing operably drivingly connecting said first and second bars and effected to move one of said bars within said housing in a given direction in response to the movement of the other of said bars in the opposite direction, and locking means independent of said driving means and comprising rotatable drive means active on said first bar and effective when actuated to move said first bar between locking and unlocking positions, said second bar, when said first bar is moved to said locking position, moving away from said first bar to a locking position, said bars then extending respectively from opposite ends of said housing and said second bar, when said first bar is moved to said unlocking position, moving inwardly towards said first bar to an unlocked position, said rotatable drive means being disposed at least partially externally of said housing and said first bar being at least partially exposed to the outside of said housing, said rotatable drive means being active on said exposed portion of said first bar and being adjustably positionable along a substantial length of said housing.

20. The security lock of claim 19, wherein said first bar is at least partially exposed to the outside of said housing, said rotatable drive means being active on said exposed portion of said first bar.

21. The security lock of claim 20, wherein said rotatable drive means comprises rack means on said exposed portion of said first bar and a rotatable pinion operatively drivingly engaging said rack means, and manually actuatable means accessible from one side of said housing and operatively connected to said pinion and effective when actuated to rotate same and key actuatable means accessible from the other side of said housing and operatively connected to said pinion and effective when actuated to rotate same.

22. The security lock of claim 19, wherein said connecting member is a relatively thin connecting rod received in said other end of stabilizing bar, and wherein said adjustable securing means comprises a set screw threadedly mounted in said stabilizing bar and adapted to engage said connecting rod,

23. The security lock of claim 22, wherein said first and second driven means comprise first and second racks respectively and said rotatable drive means comprises a pinion, and manually actuatable means extending through opposite sides of said housing and effective when actuated to rotate said pinion within said housing.

24. A double bolt securing lock for securing a door against unauthorized entry comprising a housing, first and second locking bars of substantial thickness mounted within said housing at first and second ends thereof for sliding movement therein and adopted to extend outwardly therefrom at said first and second ends, respectively, rotatable drive means mounted within said housing near said first end thereof, first driven means on said first bar operably drivingly engaging said rotatable'drive means, second driven means mounted within said housing and slidable therein and operably drivingly engaging said rotatable drive means, said rotatable drive means being effective to move said first and second driven means simultaneously, reciprocally in opposite directions, and connecting means within said housing connected to one end of said second driven means and at the other end to said second bar and effective to transmit the movement of said second driven means to said second bar, said rotatable drive means thereby being effective to simultaneously move said first and second bars between an unlocking position and a locking position extending in opposite directions outwardly of said housing, said connecting means comprising a stabilizing bar slidably mounted within said housing, means securing said stabilizing bar at one end to said second driven means, a connecting member secured at one end to said locking bar and means adjustably securing said other end of said connecting member to said other end of said stabilizing bar, and aperture means in said housing in registration with said adjustable securing means whereby said adjustable securing means is accessible through said aperture in said housing, whereby said lock may bemodified for installation on doors of various sizes. 

1. A double bolt security lock for securing a door against unauthorized entry, comprising a housing, first and second locking bars mounted in said housing for sliding movement therein, and adapted to extend outwardly therefrom at opposite ends thereof, driving means within said housing operably drivingly connecting said first and second bars and effective to move one of said bars in said housing in a given direction in response to the movement of the other of said bars in the opposite direction, locking means independent of said driving means comprising moving means operably connected to said first bar and effective when actuated to move said first bar between locking and unlocking positions, said second bar, when said first bar is moved to said locking position, moving away from said first bar to a locking position, said bars then extending respectively from opposite ends of said housing and said second bar, when said first bar is moved to said unlocking position, moving inwardly towards said first bar to an unlocked position; a lock casing, a first aperture in said housing, depressible means on said first bar and extending transversely therefrom into said first housing aperture such that said first bar is latched in said locking position whereby said opposing extending bars are deadlocked in their extended locking positions, and manually actuatable means on said lock casing movable into said housing aperture and effective when so moved to depress said depressible means to a position inwardly of said housing thereby to unlatch said first bar from said housing.
 2. The security lock of claim 1, further comprising a recess extending transversely into said first bar, said depressible means being slidably mounted within said recess, and resilient means urging said depressible means into said first housing aperture when said first bar is in said first position.
 3. The security lock of claim 2, further comprising a longitudinally extending slot in said housing communicating at one end with said first housing aperture, said manually actuatable means being said moving means and comprising a finger moveable through said first housing aperture into said recess to depress said depressible means within said recess and adapted to drivingly engage said recess and to move within said slot in said housing thereby to carry said first bar from said second to said first position.
 4. The security lock of claim 3, wherein said finger is rotatably mounted on said lock casing and is adapted to move through said slot in an arcuate path.
 5. The security lock of claim 4, further comprising a second aperture in said housing spaced from said first housing aperture and communicating with the other end of said slot, said finger being adapted to move inTo said housing through one of said apertures to traverse said slot and to move out of said housing through the other of said apertures, said second aperture receiving said depressible means in said second position of said first bar.
 6. The security lock of claim 5, wherein said bars in their unlocked positions are fully retracted within said housing.
 7. The security lock of claim 5, further comprising stop means operatively connected to said first bar and said lock casing and active therebetween to limit the travel of said first bar substantially between said first and second positions.
 8. The security lock of claim 1, wherein there are two manually actuable means each effective to move said first bar from said second to said first position, one of said manually actuatable means being accessible from one side of said lock casing and the other of said manually actuatable means being key actuatable from the other side of said lock casing.
 9. The security lock of claim 8, wherein said bars in their unlocked positions are fully retracted within said housing.
 10. The security lock of claim 1, further comprising stop means operatively connected to said first bar and said lock casing and active therebetween to limit the travel of said first bar substantially between said first and second positions.
 11. The security lock of claim 9, further comprising a recess extending transversely into said first bar, said depressible means being slidably mounted within said recess, and resilient means urging said depressible means into said first housing aperture when said first bar is in said first position.
 12. The security lock of claim 10, further comprising a recess extending transversely into said first bar, said depressible means being slidably mounted within said recess, and resilient means urging said depressible means into said first housing aperture when said first bar is in said first position.
 13. The security lock of claim 12, further comprising a longitudinally extending slot in said housing communicating at one end with said first housing aperture, said manually actuatable means being said moving means and comprising a finger moveable through said first housing aperture into said recess to depress said depressible means within said recess and adapted to drivingly engage said recess and to move within said slot in said housing thereby to carry said first bar from said second to said first position.
 14. The security lock of claim 5, wherein there are two fingers each movable through said aperture into said recess to depress said depressible means in said recess and to drivingly engage said recess and adapted to move within and along said slot in said housing thereby to move said first bar from said second to said first position, said fingers being mounted on first and second rotatable shafts within said casing, said first shaft being manually rotatable from one side of said lock casing and said second shaft being key actuatable from the other side of said casing.
 15. The security lock of claim 7, wherein there are two fingers each movable through said aperture into said recess to depress said depressible means in said recess and to drivingly engage said recess and adapted to move within and along said slot in said housing thereby to move said first bar from said second to said first position, said fingers being mounted on first and second rotatable shafts within said casing, said first shaft being manually rotatable from one side of said lock casing and said second shaft being key actuatable from the other side of said casing.
 16. The security lock of claim 1 wherein said bars in their unlocked positions are fully retracted within said housing.
 17. The security lock of claim 16, further comprising a recess extending transversely into said first bar, said depressible means being slidably mounted within said recess, and resilient means urging said depressible means into said first housing aperture when said first bar is in said first positioN.
 18. The security lock of claim 17, further comprising a longitudinally extending slot in said housing communicating at one end with said first housing aperture, said manually actuatable means being said moving means and comprising a finger moveable through said first housing aperture into said recess to depress said depressible means within said recess and adapted to drivingly engage said recess and to move within said slot in said housing thereby to carry said first bar from said second to said first position.
 19. A double bolt security lock for securing a door against unauthorized entry, comprising a housing, first and second locking bars mounted in said housing for sliding movement therein and adapted to extend outwardly therefrom at opposite ends thereof, driving means within said housing operably drivingly connecting said first and second bars and effected to move one of said bars within said housing in a given direction in response to the movement of the other of said bars in the opposite direction, and locking means independent of said driving means and comprising rotatable drive means active on said first bar and effective when actuated to move said first bar between locking and unlocking positions, said second bar, when said first bar is moved to said locking position, moving away from said first bar to a locking position, said bars then extending respectively from opposite ends of said housing and said second bar, when said first bar is moved to said unlocking position, moving inwardly towards said first bar to an unlocked position, said rotatable drive means being disposed at least partially externally of said housing and said first bar being at least partially exposed to the outside of said housing, said rotatable drive means being active on said exposed portion of said first bar and being adjustably positionable along a substantial length of said housing.
 20. The security lock of claim 19, wherein said first bar is at least partially exposed to the outside of said housing, said rotatable drive means being active on said exposed portion of said first bar.
 21. The security lock of claim 20, wherein said rotatable drive means comprises rack means on said exposed portion of said first bar and a rotatable pinion operatively drivingly engaging said rack means, and manually actuatable means accessible from one side of said housing and operatively connected to said pinion and effective when actuated to rotate same and key actuatable means accessible from the other side of said housing and operatively connected to said pinion and effective when actuated to rotate same.
 22. The security lock of claim 19, wherein said connecting member is a relatively thin connecting rod received in said other end of stabilizing bar, and wherein said adjustable securing means comprises a set screw threadedly mounted in said stabilizing bar and adapted to engage said connecting rod.
 23. The security lock of claim 22, wherein said first and second driven means comprise first and second racks respectively and said rotatable drive means comprises a pinion, and manually actuatable means extending through opposite sides of said housing and effective when actuated to rotate said pinion within said housing.
 24. A double bolt securing lock for securing a door against unauthorized entry comprising a housing, first and second locking bars of substantial thickness mounted within said housing at first and second ends thereof for sliding movement therein and adopted to extend outwardly therefrom at said first and second ends, respectively, rotatable drive means mounted within said housing near said first end thereof, first driven means on said first bar operably drivingly engaging said rotatable drive means, second driven means mounted within said housing and slidable therein and operably drivingly engaging said rotatable drive means, said rotatable drive means being effective to move said first and second driven means simultaneously, reciprocally in opposite directions, aNd connecting means within said housing connected to one end of said second driven means and at the other end to said second bar and effective to transmit the movement of said second driven means to said second bar, said rotatable drive means thereby being effective to simultaneously move said first and second bars between an unlocking position and a locking position extending in opposite directions outwardly of said housing, said connecting means comprising a stabilizing bar slidably mounted within said housing, means securing said stabilizing bar at one end to said second driven means, a connecting member secured at one end to said locking bar and means adjustably securing said other end of said connecting member to said other end of said stabilizing bar, and aperture means in said housing in registration with said adjustable securing means whereby said adjustable securing means is accessible through said aperture in said housing, whereby said lock may be modified for installation on doors of various sizes. 